SAP Message BRF458 - Specify a reference expression (result type R)

System Response
The current expression expects you to enter a subexpression whose resulttype is R (reference-like expression).

Procedure
Enter a subexpression with result type R.
Note: You can use the expression type Reference-Like Expression(implementing class 0RF001). Alternatively, you can configure theexpression type Simple Value Request (0SM001) so that it deliversa result of type R .